Sox9 在人普通型与去分化型软骨肉瘤差异表达*

目的:探讨Sox9 在人普通软骨肉瘤，去分化软骨肉瘤和正常软骨中的表达。方法:取12例2003年1 月至2007年1 月在北京大学人民医院经病理切片确诊为软骨肉瘤（普通软骨肉瘤6 例，去分化软骨肉瘤6 例）及正常软骨组织（6 例）的新鲜冰冻标本，利用基因芯片的方法分析后，将Sox9 作为候选基因，而后利用Real-time PCR，Western blot和免疫组化的方法比较其在人普通软骨肉瘤，去分化软骨肉瘤和正常软骨组织中的差异表达。结果:基因芯片结果显示:与正常软骨组织相比，Sox9 在普通软骨肉瘤中上调约1.6 倍，在去分化软骨肉瘤中，其表达水平为正常软骨组织表达水平的0.082 倍；Real-time PCR检测结果显示:Sox9mRNA 在普通软骨肉瘤和去分化软骨肉瘤中表达水平分别为1.68± 0.119 和0.088 ± 0.017；Western blot分析表明Sox9 蛋白在人普通软骨肉瘤的表达量明显高于正常软骨组织，在去分化软骨肉瘤中的表达量显著低于正常软骨组织。免疫组化实验结果表明与正常软骨组织相比，6 例普通软骨肉瘤均有Sox9 表达，细胞染色呈较强的阳性，而去分化软骨肉瘤未发现较强阳性细胞出现，只有可疑的阳性细胞散在出现。结论:Sox9 在普通软骨肉瘤中的表达水平明显高于正常软骨组织，在去分化软骨肉瘤中的表达水平显著低于正常软骨组织。Sox9 在去分化软骨肉瘤中低水平表达与去分化软骨肉瘤疾病进展快，预后差呈正向相关。 

Differential Expression of Sox9 in Conventional Chondrosarcoma and Dedifferentiated Chondrosarcoma

Objective: To investigate the differential expression of Sox9 in conventional chondrosarcoma,dedifferentiated chondrosarcoma and normal cartilage. Methods: We reported 12 cases of chondrosarcomas,which were initially diagnosed as chondrosarcomas(6 cases of conventional chondrosarcoma and 6 cases of dedifferentiated chondrosarcoma)at Peking University People's Hospital between January 2003 and January 2007.We used genechip method to identify difierentially expressed genes involved in conventional chondrosarcoma,dedifferentiated chondrosarcoma and in normal cartilage(6 cases)and found thousands of differentially expressed genes after extensive statistical analysis.With Sox9 which played crucial roles in the process of both differentiation and maturation of chondrocyte as a candidate,we used Real-time PCR,Westem blot and immunohistochemistry to confirm the results found by gene chip. Results: DNA microarray results showed that Sox9 was up-regulated about 1.6 times in conventional chondrosarcoma compared with that in normal cartilage.But in dedifferentiated chondrosarcoma,the expression level of Sox9 was significantly down-regulated,0.082 times of that in normal cartilage.Real-time PCR results showed that the expression levels of Sox9 mRNA in conventional chondrosarcomas and dedifferentiated chondrosarcomas were 1.68±0.119 and 0.088±0.017,respectively.Sox9 protein level was significantly higher in humen conventional chondrosarcomas than that in normal cartilage.Sox9 protein level in dedifferentiated chondrosarcomas was significantly lower than that in normal cartilage tissue.All of the 6 cases of conventional chondrosarcomas showed diffuse and strong staining of Sox9.However,Only scattered staining was observed in dedifferentiated chondrosarcomas. Conclusion: Compared with that in normal cartilage,Sox9 expression is up-regulated in conventional chondrosarcomas and down-regulated in dedifferentiated chondrosarcomas.Decrease of Sox9 expression in dedifferentiated chondrosarcoma is correlated with poor survival,indicating that Sox9 may serve as a molecular prognostic marker for chondrosarcomas and disease progression.